JP2007139687A - Probe card - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a probe card provided with the first substrate connected to a contact probe, and the second substrate arranged opposedly to the first substrate, and capable of connecting surely the first substrate electrically to the second substrate. <P>SOLUTION: An annular conductive member 6 is arranged between the first substrate 4 and the second substrate 5, and the first substrate 4 is connected electrically to the second substrate 5 by bringing a top part and a bottom part of the conductive member 6 into contact respectively with an upper electrode 42 of the contact substrate 4 and a lower electrode 52 of the main substrate 5. An elastomer 61 is filled in a hollow portion of the conductive member 6. A shift of an abutting part between the electrodes 42, 52 caused by thermal deformation is reduced compared with that in constitution of bringing an end part of a contact formed into a slender shape into contact with the electrodes, because the conductive member 6 is formed annularly. The first substrate 4 is surely connected electrically to the second substrate 5, by this manner. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a probe card, and more particularly, to an improvement in an electrical connection structure between a contact substrate on which a contact probe is formed and a main substrate holding the contact substrate.

  As an example of an apparatus for performing electrical connection with an electrode of a semiconductor device, a probe card that performs electrical connection by bringing a contact probe (contact probe) into contact with an inspection target such as a semiconductor integrated circuit is known. It has been. A probe card is generally configured by arranging a large number of contact probes on a substrate in accordance with the number and pitch of electrodes of a semiconductor integrated circuit.

  The probe card includes a contact substrate as a first substrate having a contact probe formed on the front surface, and a main substrate as a second substrate that is arranged to face the contact substrate and holds the contact substrate. (For example, Patent Document 1). The electrical connection between the contact probe on the contact substrate and the wiring on the main substrate can be performed by an electrical connection means called an interposer provided between the contact substrate and the main substrate. The interposer is configured as a unit including, for example, a plurality of connectors whose both ends are in contact with the contact substrate and the main substrate, and a support plate that integrally holds these connectors.

The contact probe contacts the inspection object at its tip. More specifically, the contact probe is brought close to the vertical direction with respect to the electrode of the inspection object arranged parallel to the contact substrate, and the tip of the contact probe is brought into contact. Thereafter, by further pressing the contact probe, so-called overdrive is performed, and all the contact probes can be reliably brought into contact with the electrodes of the inspection object.
JP 2004-119945 A

  Usually, the connector of the interposer is formed in an elongated shape that can be elastically deformed by using a forming method such as so-called wire bonding. However, when the connector is formed in an elongated shape in this way, when the probe card is used in a high temperature environment, the tip position is shifted due to thermal deformation of the connector, and the electrical connection between the contact substrate and the main substrate is lost. In some cases, general connection could not be performed well.

  The present invention has been made in view of the above circumstances, and includes a first substrate connected to a contact probe, and a second substrate disposed to face the first substrate, and the first substrate and the first substrate It is an object of the present invention to provide a probe card capable of more reliably performing electrical connection with two substrates.

  A probe card according to a first aspect of the present invention includes a first substrate having a first electrode connected to a contact probe, a second substrate disposed opposite to the first substrate, and disposed opposite to the first electrode. An annular conductive member disposed between a second substrate having an electrode, the first electrode and the second electrode, and a top portion and a bottom portion contacting the first electrode and the second electrode, respectively; A connection portion in which a hollow portion of the annular conductive member is filled with an elastic body is provided.

  With such a configuration, by arranging the annular conductive member between the first substrate and the second substrate, the top and bottom of the conductive member are brought into contact with the first electrode and the second electrode, respectively, and the first Electrical connection between the substrate and the second substrate can be performed. Since the conductive member is formed in an annular shape, the displacement of the contact portion with the electrode due to thermal deformation is reduced as compared with a configuration in which the end portion of the connector formed in an elongated shape is in contact with the electrode. be able to. Therefore, electrical connection between the first substrate and the second substrate can be more reliably performed.

  Also, by filling the hollow part of the conductive member with an elastic body, the strength against the external force applied to the outer peripheral surface of the conductive member can be increased, compared with the case where the internal space of the annular conductive member is hollow. It is possible to prevent the conductive member from being deformed by applying excessive pressure.

  In the probe card according to the second aspect of the present invention, the top and bottom of the annular conductive member are joined to the first electrode and the second electrode, respectively. With such a configuration, it is possible to prevent the position of the conductive member from being shifted with respect to the first electrode and the second electrode, so that the electrical connection between the first substrate and the second substrate can be more reliably performed.

  In the probe card according to the third aspect of the present invention, a part of the outer peripheral surface of the annular conductive member is cut away. With such a configuration, the conductive member can be held by locking the holding tool in the notch formed on the outer peripheral surface of the conductive member, so that the conductive member is interposed between the first substrate and the second substrate. The arrangement | positioning work can be performed easily.

  According to the present invention, by arranging an annular conductive member between the first substrate and the second substrate, the top and bottom of the conductive member are brought into contact with the first electrode and the second electrode, respectively, Electrical connection between the substrate and the second substrate can be performed. Since the conductive member is formed in an annular shape, the displacement of the contact portion with the electrode due to thermal deformation is reduced as compared with a configuration in which the end portion of the connector formed in an elongated shape is in contact with the electrode. be able to. Therefore, electrical connection between the first substrate and the second substrate can be more reliably performed.

Embodiment 1 FIG.
FIG. 1 is a side view showing an example of a probe card 1 according to Embodiment 1 of the present invention, and shows a state before contact with a silicon wafer 2 as an inspection object. The probe card 1 includes a contact substrate 4 as a first substrate and a main substrate 5 as a second substrate. A large number of contact probes 3 as electrical contacts are formed on the lower surface of the contact substrate 4. The main substrate 5 is disposed so as to face the upper surface of the contact substrate 4 and holds the contact substrate 4.

  The contact substrate 4 is made of a thin silicon substrate formed in a rectangular flat plate shape, and a large number of contact probes 3 are arranged in a plurality of rows on the lower surface as the front surface. The contact probes 3 in each row are aligned at regular intervals along the front-rear direction in FIG. A large number of lower electrodes 41 are arranged in a lattice pattern on the lower surface of the contact substrate 4, and the contact probes 3 are coupled to the lower electrodes 41.

  On the upper surface as the back surface of the contact substrate 4, a large number of upper electrodes 42 are arranged in a lattice pattern so as to face the lower electrodes 41. Each upper electrode 42 is electrically connected to the corresponding lower electrode 41 through a wiring 43 that penetrates the contact substrate 4.

  The main substrate 5 is made of a glass epoxy substrate formed in a circular flat plate shape larger than the contact substrate 4, and the contact substrate 4 is opposed to the lower part of the central portion thereof. The contact substrate 4 is attached to the lower surface of the main substrate 5 by a fixture 51 so as to face downward with a predetermined interval.

  A large number of lower electrodes 52 are arranged in a lattice shape at the center of the lower surface of the main substrate 5 so as to face the upper electrodes 42 of the contact substrate 4. Further, upper electrodes 53 corresponding to the respective lower electrodes 52 are formed on the upper surface of the main substrate 5. The interval between the adjacent upper electrodes 53 is arranged to be wider than the interval between the lower electrodes 52, and the main substrate so that the corresponding lower electrode 52 and upper electrode 53 expand toward the peripheral side. 5 is electrically connected by a wiring 54 penetrating the inside of the wire 5.

  The upper electrode 42 of the contact substrate 4 and the lower electrode 52 of the main substrate 5 are each formed in a flat plate shape, and a circle is formed between the upper electrode 42 and the lower electrode 52 facing each other in the vertical direction. A conductive member 6 made of an annular metal is disposed. Each conductive member 6 is arranged in a posture facing the same direction, and the top and bottom of each conductive member 6 come into contact with the upper electrode 42 and the lower electrode 52, respectively, so that the contact substrate is interposed via each conductive member 6. 4 and the main board 5 are electrically connected. That is, each conductive member 6 constitutes a connection portion 10 for electrically connecting the contact substrate 4 and the main substrate 5. The top and bottom of each conductive member 6 are joined to the upper electrode 42 and the lower electrode 52 by soldering.

  The hollow portion of each conductive member 6 is filled with an elastic body 61 made of, for example, elastic resin. Accordingly, each conductive member 6 is configured to be elastically deformable with respect to an external force acting from the outer peripheral surface toward the center, and is held in a distorted state between the upper electrode 42 and the lower electrode 52. .

  Each upper electrode 53 of the main substrate 5 is electrically connected to a tester device (not shown). At the time of inspection, the silicon wafer 2 is placed on the movable table 7 with the surface on which the integrated circuit is formed facing up, so that the electrodes 21 of the silicon wafer 2 are arranged horizontally. Then, the movable table 7 is moved or rotated in the horizontal plane to align the contact probe 3 and the silicon wafer 2, and then the movable table 7 is raised to bring the contact probe 3 into contact with the silicon wafer 2, and the tester device The electrical characteristics of the integrated circuit are inspected.

  Thus, the probe card 1 approaches the silicon wafer 2 arranged in parallel to the lower surface thereof in the vertical direction, and the tip of the contact probe 3 contacts the electrode 21 of the silicon wafer 2. At this time, only a tip portion of the contact probe 3 comes into contact with the electrode 21 due to a vertical shift based on an attachment error of the electrode 21 of the silicon wafer 2. Thereafter, by further pressing the contact probe 3, so-called overdrive is performed, and all the contact probes 3 can be reliably brought into contact with the electrode 21 of the silicon wafer 2.

  In the present embodiment, by arranging the annular conductive member 6 between the contact substrate 4 and the main substrate 5, the top and bottom portions of the conductive member 6 are respectively connected to the upper electrode 42 of the contact substrate 4 and the main substrate 5. The contact substrate 4 and the main substrate 5 can be electrically connected by contacting the lower electrode 52. Since the conductive member 6 is formed in an annular shape, the contact portion with the electrodes 42 and 52 due to thermal deformation is compared with a configuration in which the end portion of the connector formed in an elongated shape is in contact with the electrode. Deviation can be reduced. Therefore, the electrical connection between the contact substrate 4 and the main substrate 5 can be more reliably performed.

  Further, since the top and bottom of the conductive member 6 are joined to the upper electrode 42 of the contact substrate 4 and the lower electrode 52 of the main substrate 5, the position of the conductive member 6 with respect to the upper electrode 42 and the lower electrode 52. Prevents slippage. Therefore, the electrical connection between the contact substrate 4 and the main substrate 5 can be more reliably performed.

  Further, since the elastic body 61 is filled in the internal space of the conductive member 6, the strength against the external force applied to the outer peripheral surface of the conductive member 6 can be increased, and the internal space of the annular conductive member 6 is hollow. As compared with the above, it is possible to suppress the conductive member 6 from being deformed by applying an excessive pressure.

  FIG. 2 is a view schematically showing a manufacturing process of the conductive member 6 of FIG. When manufacturing the conductive member 6, first, a cylindrical metal rod 62 is immersed in a plating solution, and a direct current is passed through the metal rod 62, so that a metal is applied to the surface of the metal rod 62 by a so-called electroplating method. Precipitate. As a result, as shown in FIG. 2A, a cylindrical body 63 made of a metal film is formed on the surface of the metal rod 62.

  Thereafter, as shown in FIG. 2B, the metal rod 62 is pulled out from the formed cylindrical body 63. Then, as shown in FIG. 2 (c), after the elastic body 61 is filled in the internal space of the cylindrical body 63, it is cut into rounds at regular intervals on a plane orthogonal to the axial direction. As shown, a large number of annular conductive members 6 in which the internal space is filled with the elastic body 61 can be manufactured. The conductive member 6 has an outer diameter of 70 μm, an inner diameter of 50 μm, a thickness of 10 μm, and an axial width of 40 μm, and can be formed of a metal material such as nickel.

  However, the method is not limited to the method in which the cylindrical body 63 is formed and the inner space of the cylindrical body 63 is filled with the elastic body 61. After the cylindrical elastic body 61 is formed, the surface of the elastic body 61 is made of metal. A method of forming the cylindrical body 63 made of a film may be used.

  FIG. 3 is a diagram for explaining an example of a method for disposing the conductive member 6 between the contact substrate 4 and the main substrate 5. In this example, in order to dispose a large number of conductive members 6 between the contact substrate 4 and the main substrate 5 at once, a holding plate 8 formed into a thin plate shape with a heat-resistant resin such as polyimide is used. FIG. 3A is a perspective view of the holding plate 8 viewed obliquely from above, and FIG. 3B is a cross-sectional view taken along line AA in FIG.

  As shown in FIG. 3A, the holding plate 8 has a plurality of rectangular openings 81 formed in a lattice pattern. Each opening 81 has a short side that is substantially the same as the thickness of the conductive member 6, and a long side that is shorter than the diameter of the conductive member 6. Therefore, the holding plate 8 is leveled, and the conductive member 6 filled with the elastic body 61 is inserted into each opening 81 from above, thereby holding the conductive member 6 in a state where a part of the conductive member 6 is fitted in each opening 81. be able to.

  In a state where the conductive member 6 is fitted in the opening 81, the lower portion of the conductive member 6 projects below the holding plate 8 as shown in FIG. Therefore, the holding plate 8 is disposed between the contact substrate 4 and the main substrate 5 with the conductive member 6 fitted in each opening 81 of the holding plate 8, and the lower portion of each conductive member 6 is located above the contact substrate 4. By soldering the upper part of each conductive member 6 to the electrode 42 and the lower electrode 52 of the main substrate 5, a large number of the conductive members 6 can be attached at a time between the upper electrode 42 and the lower electrode 52. .

  In the first embodiment, the configuration in which the internal space of the conductive member 6 is filled with the elastic body 61 has been described. However, if the step of FIG. An unfilled conductive member 6 can be obtained, and the conductive member 6 can be disposed between the contact substrate 4 and the main substrate 5. Even in such a case, by using the holding plate 8 as shown in FIG. 3 and fitting the conductive member 6 into each opening 81, a large number of the conductive members 6 can be attached to the upper electrode 42 and the lower electrode 52. Can be easily installed in between.

Embodiment 2. FIG.
FIG. 4 is a diagram for explaining an example of a configuration and an arrangement method of the conductive member 6 according to the second embodiment of the present invention. In this example, a notch 65 is formed in a part of the outer peripheral surface of the conductive member 6 as shown in FIG.

  The notch 65 is formed in a part other than the top and bottom of the conductive member 6, for example, the right side or the left side, and is formed in a shape that tapers toward the center of the conductive member 6. The notch 65 penetrates the outer peripheral surface of the conductive member 6 and reaches the elastic body 61 filled in the internal space. Thus, by forming the notch 65 in a part of the outer peripheral surface of the conductive member 6, the conductive member 6 is substantially C-shaped.

  When the conductive member 6 is disposed between the contact substrate 4 and the main substrate 5, the thin wire-shaped holding rod 9 is engaged with the notch 65 of the conductive member 6, so that the holding rod 9 is interposed therebetween. The conductive member 6 is held and moved between the contact substrate 4 and the main substrate 5. At this time, as shown in FIG. 4B, two or more conductive members 6 are arranged on the same axis, and the notches 65 are arranged in the axial direction so that the linear holding rod 9 is connected to each conductive member. By engaging the notch 65 in the number 6, a large number of conductive members 6 can be held simultaneously.

  In the present embodiment, since the holding member 9 can be held in the notch 65 formed on the outer peripheral surface of the conductive member 6 and the conductive member 6 can be held, the gap between the contact substrate 4 and the main substrate 5 can be maintained. Thus, the work of arranging the conductive member 6 can be easily performed.

Embodiment 3 FIG.
FIG. 5 is a side view showing a configuration example of the conductive member 6 according to Embodiment 3 of the present invention, and shows a configuration in which a flat surface 64 is formed on the outer peripheral surface of the conductive member 6.

  In the example of FIG. 5A, a flat surface 64 extending in the tangential direction is formed only at one place on the outer peripheral surface of the annular conductive member 6, and the flat surface 64 is formed on the upper electrode 42 of the contact substrate 4. It arrange | positions so that it may contact | abut. However, the conductive member 6 may be arranged so that the flat surface 64 contacts the lower electrode 52 of the main substrate 5 by rotating the conductive member 6 180 degrees from the state shown in FIG.

  In the example of FIG. 5B, flat surfaces 64 extending in the tangential direction are formed at two locations on the outer peripheral surface of the annular conductive member 6. These flat surfaces 64 are arranged symmetrically about the axis of the conductive member 6 and extend parallel to each other. The conductive member 6 is disposed such that one flat surface 64 contacts the upper electrode 42 of the contact substrate 4 and the other flat surface 64 contacts the lower electrode 52 of the main substrate 5.

  In the present embodiment, the conductive member 6 is stably attached to the upper electrode 42 of the contact substrate 4 or the lower electrode 52 of the main substrate 5 via the flat surface 64 formed on the outer peripheral surface of the annular conductive member 6. While being able to contact, a contact area can be enlarged. The flat surface 64 is formed on the outer peripheral surface of the conductive member 6 in such a manner that a cutting means is provided along the axial direction with respect to the outer peripheral surface of the cylindrical body 63 in the step of pulling out the metal rod 62 shown in FIG. This can be easily done by slicing in contact.

  However, the present invention is not limited to the configuration of the present embodiment, and in the conductive member 6 in which the notch 65 is formed as shown in FIG. 4, the flat surface 64 is formed at the top or bottom, and the flat surface 64 is formed. You may arrange | position so that the upper electrode 42 of the contact board | substrate 4 or the lower electrode 52 of the main board | substrate 5 may be contact | abutted.

  In the above embodiments, the case where the conductive member 6 is formed in an annular shape has been described. However, the present invention is not limited to such a configuration, and the conductive member is formed in an annular shape having a polygonal shape. Also good. In this case, the conductive member has a 2n square shape (n is an integer of 2 or more) so that parallel flat surfaces are formed in contact with the upper electrode 42 of the contact substrate 4 and the lower electrode 52 of the main substrate 5, respectively. It is preferable that it consists of.

  Although the configuration in which the probe card 1 contacts the silicon wafer 2 from above has been described with reference to FIG. 1, the probe card 1 is in a state where the front surface on which the contact probe 3 is formed faces upward, that is, FIG. It is also possible to use it with the top and bottom reversed with respect to 1.

  Moreover, although the above embodiment demonstrated the case where the probe card 1 was made to contact the silicon wafer 2 as an example of a test object, this probe card 1 is not restricted to semiconductor integrated circuits, such as the silicon wafer 2, It can also be used in contact with electrodes of other semiconductor devices.

It is the side view which showed an example of the probe card by Embodiment 1 of this invention, and has shown the state before contact with the silicon wafer as a test object. It is the figure which showed schematically the manufacturing process of the electrically-conductive member of FIG. It is a figure for demonstrating an example of the method of arrange | positioning a electrically-conductive member between a contact board | substrate and a main board | substrate. It is a figure for demonstrating the example of a structure of the electrically-conductive member by Embodiment 2 of this invention, and an example of the arrangement | positioning method, and has shown the structure by which the notch was formed in a part of outer peripheral surface of an electrically-conductive member. It is the side view which showed the structural example of the electrically-conductive member by Embodiment 3 of this invention, and has shown the structure by which the flat surface was formed in the outer peripheral surface of an electrically-conductive member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Probe card 2 Silicon wafer 3 Contact probe 4 Contact board 5 Main board 6 Conductive member 8 Holding plate 9 Holding rod 10 Connection part 21 Electrode 41 Lower electrode 42 Upper electrode 43 Wiring 52 Lower electrode 53 Upper electrode 54 Wiring 61 Elastic body 64 Flat surface 65 Notch 81 Opening

Claims (3)

A first substrate having a first electrode connected to a contact probe;
A second substrate disposed opposite the first substrate and having a second electrode disposed opposite the first electrode;
The annular conductive member is disposed between the first electrode and the second electrode, and the top and the bottom are in contact with the first electrode and the second electrode, respectively, and the hollow portion of the annular conductive member And a connecting portion filled with an elastic body.   The probe card according to claim 1, wherein a top portion and a bottom portion of the annular conductive member are joined to the first electrode and the second electrode, respectively.   3. The probe card according to claim 2, wherein a part of the outer peripheral surface of the annular conductive member is cut out.

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